A Microwatt-Class Always-On Sensor Fusion Engine Featuring Ultra-Low-Power AOI Clocked Circuits in 14nm CMOS

A microwatt-class always-on sensor fusion engine is fabricated in 14nm CMOS and occupies 0.024mm2. Robust ultra-low-voltage And-Or-Invert (AOI) latch, integrated clock gate (ICG), flip-flop (FF) circuits achieve 19% clock power reduction with 100mV improved V MIN . Single-instruction matrix operations, complex fixed-point SIMD instructions with inline shift/permute, programmable power gates, and AOI clocked circuits enable near-threshold voltage energy consumption of 19nJ/iteration for 9-Degrees-of-Freedom (DoF) Kalman filter orientation estimation at 360mV, 25 °C.